On Thu, 2 Apr 2020 08:33:42 -0400, Mirko Vukovic said:
On Thu, Apr 2, 2020 at 7:55 AM Martin Simmons martin@lispworks.com wrote:
> On Wed, 1 Apr 2020 08:59:30 -0400, Mirko Vukovic said:
On Tue, Mar 31, 2020 at 11:51 AM Martin Simmons martin@lispworks.com wrote:
>>> On Mon, 30 Mar 2020 21:16:00 -0400, Mirko Vukovic said:
Hello,
My setup is Sly on Spacemacs with Windows 10 running remote lisp on
Linux
over a corporate network. I have not found a Sly mailing list, and I
hope I
can get an answer here.
Emacs is running Sly on Spacemacs on Windows 10. Lisp is running on a
Linux
server. But Sly does not connect to the listening Lisp. Corporate
network
security policies have changed. I can ask for IT to accommodate me,
but
first I need to know what to ask for.
So far, I have opened a tunnel, and started a listening lisp (details below).
In Emacs I get:
sly-connect RET RET RET [sly] Connecting to Slynk on port 4005.. helm-M-x-execute-command: make client process failed: Connection
timed
out,
:name, sly-9, :buffer, nil, :host, hal9000, :service, 4005, :nowait,
nil,
:tls-parameters, nil
The session transcript:
ssh -L4005:localhost:4005 mirko@hal9000
[mirko@hal9000 .roswell]$ ros -L ccl-bin run --load
start-slynk-server.lisp
Added SLYNK path to ASDF:*CENTRAL-REGISTRY* SLYNK's ASDF loader finished. Loaded ASDF system ;; Slynk started at port: 4005.
Created SLYNK server on port 4005 Set *USE-DEDICATED-OUTPUT-STREAM* to NIL Clozure Common Lisp Version 1.11.5/v1.11.5 (LinuxX8664)
For more information about CCL, please see http://ccl.clozure.com.
CCL is free software. It is distributed under the terms of the
Apache
Licence, Version 2.0. ?
My question is as follows:
- Do I need bi-directional traffic on 4005?
Assuming you are using the ssh tunnel above, then you don't need port
4005
traffic on the LAN (it is all hidden in the tunnel).
The most likely problem is that some firewall on the Windows machine is blocking port 4005. You may need to configure that firewall to allow
ssh
to listen on localhost:4005 and/or to accept connections to it from
Spacemacs.
In theory you might have similar localhost firewall issues on hal9000,
but
that is less likely.
- Do I need bi-directional traffic on 22? (after recent changes I
cannot ssh or scp into my Windows machine)
I'm assuming that you ran the ssh command on the Windows 10 machine
and it
gave you a working login to hal9000. If so, then it looks like you
already
have what you need for port 22.
Yes, I can log in to hal9000 with the -L switch:
ssh -L4005:localhost:4005 mirko@hal9000
Last login: Thu Mar 19 14:33:17 2020 from 172.27.236.189 [mirko@hal9000 ~]$
Note that bi-directional traffic on a connected socket is different
from
whether you can make a connection in both directions.
- What tools can I use to try to narrow down the cause of the
problem?
For instance, can I send a command to the lisp image, and see its
effects
on the lisp side?
Firstly, run "netstat -antp" on hal9000 to see if Lisp is listening on
port
It looks that ccl-bin is listening: $ sudo netstat -antp | grep :4005 tcp 0 0 127.0.0.1:4005 0.0.0.0:*
LISTEN
104461/lx86cl64Secondly, run "netstat -anop tcp" on the Windows 10 machine to see if
ssh
is listening on port 4005.
I have Msys2's netstat. On the laptop:
which netstat
/c/WINDOWS/system32/netstat /c/Users/mirko/Downloads
netstat -anop tcp | grep :4005
TCP 127.0.0.1:4005 0.0.0.0:0 LISTENING
12052
Yes, both netstat outputs look good at that point.
Thirdly, run "ssh -p 4005 localhost" on the Windows 10 machine. This
use a
ssh is very bogus, but it should at least give an error message with
some
diagnostics. (Normally I would use telnet for this, but it is not installed on Windows 10 by default.)
Outputs of both ssh and telnet on the laptop:
which telnet
/usr/bin/telnet /c/Users/mirko/Downloads
telnet localhost 4005
Trying ::1... Connected to localhost. Escape character is '^]'. Connection closed by foreign host.
OK, so it is connected to the Windows side at least.
Check that the Slynk server was created with :dont-close t (or set slynk:*dont-close* to t before creating it). If dont-close is nil, it will only accept one connection, which makes debugging difficult.
Then restart the log in to hal9000 with -v option to ssh to make it print debug information:
ssh -v -L4005:localhost:4005 mirko@hal9000
and try the telnet again to see what is happening at the Linux end.
__Martin
Here is the test log. Telnet and ssh debug are at the bottom. 1 Start slynk with :dont-close t
Modified startup script:
(let ((port 4005)) (slynk:create-server :port port :dont-close t) (format t "~% Created SLYNK server on port ~a" port)) (setf slynk:*use-dedicated-output-stream* nil)
2 Started tunnel with verbose option, -v switch
$ ssh -v -L4005:hal9000:4005 mirko@hal9000
3 Telnet on laptop side to laptop port 4005
@laptop> telnet localhost 4005 Trying ::1... Connected to localhost. Escape character is '^]'. Connection closed by foreign host.
4 SSH debug output
@hal9000> debug1: Connection to port 4005 forwarding to hal9000 port 4005 requested. debug1: channel 3: new [direct-tcpip] channel 3: open failed: connect failed: Connection refused debug1: channel 3: free: direct-tcpip: listening port 4005 for hal9000 port 4005, connect from ::1 port 64100 to ::1 port 4005, nchannels 4
It looks like hal9000 is resolving to the IPv6 localhost address ::1 on hal9000, but the Lisp is probably only listening on IPv4.
Try restarting the tunnel with -L4005:127.0.0.1:4005 to force IPv4.
__Martin